1A5/Repairs: Difference between revisions
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Serial Number B124386 | Serial Number B124386 | ||
SYMPTOM: Vc has long asymptotic tail | ===SYMPTOM: Vc has long asymptotic tail=== | ||
DATE: 20220520<br/> | DATE: 20220520<br/> | ||
NOTE: Old symptom, just noticed now<br/> | NOTE: Old symptom, just noticed now<br/> | ||
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FIXED | FIXED | ||
SYMPTOM: Clear V/CM knob skirt is cracked and slipping | ===SYMPTOM: Clear V/CM knob skirt is cracked and slipping=== | ||
DATE: 202205<br/> | DATE: 202205<br/> | ||
NOTE: Old symptom, just slowly getting worse<br/> | NOTE: Old symptom, just slowly getting worse<br/> | ||
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OOPS: Super glue dissolved a mark<br/> | OOPS: Super glue dissolved a mark<br/> | ||
ACTION: Redraw with Sharpie<br/> | ACTION: Redraw with Sharpie<br/> | ||
[[Category:Instrument repair reports]] | |||
Revision as of 06:43, 1 November 2022
Design mistake. The UNCAL lamp is powered by "+100V DCPLD A" which shifts the trace about 0.1 division. It should be powered from the basic +100V rail.
Serial Number B124386
SYMPTOM: Vc has long asymptotic tail
DATE: 20220520
NOTE: Old symptom, just noticed now
CAUSE: Leakage in C114, 1uF 25V NP aluminum electrolytic
ACTION: Replace with 1uF 25V X7R ceramic a la Type W
FIXED
SYMPTOM: Clear V/CM knob skirt is cracked and slipping
DATE: 202205
NOTE: Old symptom, just slowly getting worse
NOTE: Part #74 in mechanical diagram, 366-0418-00
ACTION: Super-glue plastic hub to metal hub
OOPS: Super glue dissolved a mark
ACTION: Redraw with Sharpie